Electron tube mounting member



Sept. 16, 1969 E. L. TIBBETTS 3,467,769

ELECTRON TUBE MOUNTING MEMBER Filed Dec. 22, 1967 FIG. 1

INVENTOR.

ERNEST L. T/BBETTS A TTORNE Y United States Patent O1 ice 3,467,769 Patented Sept. 16, 1969 3,467,769 ELECTRON TUBE MOUNTING MEMBER Ernest L. Tibbetts, Somerville, N.J., assignor to Burroughs Corporation, Detroit, Mich., a corporation of Michigan Filed Dec. 22, 1967, Ser. No. 694,027 Int. Cl. H01b 17/56 US. Cl. 174-138 3 Claims ABSTRACT OF THE DISCLOSURE The disclosure is of an insulating disk adapted to be coupled to an electron tube having flexible leads, with the leads of the tube straightened and separated and insulated from each other by being passed through apertures in the disk. Thus, leads which are normally closely spaced and in danger of contacting each other can be safely and easily spread apart and insulated from each other.

Background of the invention There are some types of electron tubes, for example, cathode glow display tubes, which have a relatively large number of electrodes and a corresponding number of electrode leads extending through the tube envelope. As with other electronic devices, tubes of this type have become smaller and smaller, and, at the present time, one type of tube is approximately one-half inch in diameter. This tube normally contains ten numeral cathodes and an anode, each of which has its own lead extending through the tube base. These leads are usually thin, flexible wires, and they are usually oriented in two closely-spaced rows, and, as a result, the leads are easily bent and can become entwined with each other during handling. Thus, it can be seen that arranging the leads so that the tube can be mounted on a socket or printed circuit board and maintaining the leads spaced and insulated from each other are not simple matters to achieve.

Summary of the invention Briefly, the invention comprises an insulating disk which is relatively easily coupled to the flexible leads of an electron tube and straightens the leads and holds the leads separated and insulated from each other.

Description of the drawing In the drawing:

FIG. 1 is a sectional elevational view of one embodiment along lines 11 in FIG. 2 showing the invention and a portion of an electron tube with which it is used;

FIG. 2 is a plan view of said one embodiment of the invention; I

FIG. 3 .is a sectional view along the lines 33 in FIG. 2;

FIG. 4 is a view of the bottom of the tube shown in FIG. 1 to show a typical distribution of leads; and

FIG. 5 is a sectional elevational view of a modification of the invention and a portion of a tube with which it is used.

Description of the preferred embodiments Apparatus embodying the invention comprises adisk of synthetic resinous material having a diameter substantially equal to that of the electron tube to which it is coupled. It is assumed for purposes of illustration that the electron tube may include as many as fourteen flexible leads which extend from the base 32 of the tube and are oriented in two parallel rows, with the individual leads being staggered from each other. One or more leads 30 may be positioned near the periphery of the base of the tube, if desired, (FIG. 4).

One embodiment of the invention is adapted to be used with an electron tube in which the rim 40 of the base of the tube projects beyond the rest of the base which then appears as a depression surrounded by the rim (FIG. 1). For this type of tube, the insulating disk 10 has its top surface 50 provided with a raised central region 60 surrounded by a lower-level peripheral portion 70 on which tube rim 40 rests. The raised portion 60 of disk 10 rises toward, but is spaced from, the depressed base of the tube.

The disk 10 is provided with two rows of parallel lead receiving apertures 72 closely spaced to a diameter of disk 10 and one or more auxiliary apertures 72 on each side of each row of apertures 72 have relatively large orifices in the top surface and relatively small throats ending in the bottom surface, resulting in at least part of the sides of the apertures being tapered. One such tapered surface in each aperture slopes outwardly with respect to the center of the disk 10, toward the throat of the aperture and the slope of the latter surfaces decreases in steepness from aperture to aperture outwardly from the center toward the periphery of the disk 10. This construction facilitates lead insertion into the disk and forces the closely spaced leads of the tube apart for insertion into a circuit board or the like. The tapered surfaces are terminated at the top of the throat portions. Each throat has an axis parallel to the others and perpendicular to the bottom surface. The leads of the tube, therefore, are aligned parallel to one another and perpendicular to the bottom surface upon being drawn through the apertures.

The lower surface of the disk is provided with three or four raised bumps or legs to permit the disk 10 to be supported above the surface of a printed circuit board or a chassis or the like to which the tube 20 is to be attached.

In using the disk 10, the various tube leads 30 are inserted in the apertures 72 in the disk and are drawn through. Of course, any tube leads such as leads 30" which lie closer to apertures 72 then apertures 72 are inserted in these auxiliary apertures. The leads 30 nearest the center of the base are inserted in the centermost apertures 72, and the adjacent leads are inserted in the adjacent apertures. Because of the spacing of the various apertures 72 and their relative slopes, all of the leads are spaced a convenient and safe distance from each other. An auxiliary advantage of the invention arises from the fact that the relatively fine flexible leads, which tend to bend and kink easily, are also straightened as they are drawn through the apertures in disk 10 because of the parallel alignment of the small diameter throats in the bottom surface. The tube 20 mounted on disk 10 is usually soldered to printed circuit board 73 or the like.

One tube with which disk 10 has been used had leads .014 in diameter and spaced apart .040" center-to-center. It is to be understood that no attempt is made to illustrate these dimensions to scale in the drawing. In addition, the slant or orientation of the tube leads as they enter the holes in disk 10 may be different from tube to tube and need not be exactly as shown.

As shown in FIGURE 4, the throats of the apertures in the lower surface of one row may be advantageously offset from the throats of the apertures in the other row.

Referring to FIG. 5, another form of tube with which the invention may be used includes a fiat base from which the flexible leads extend. For use with this type of tube, the insulating disk 10 has a top surface which includes a peripheral rim elevated above a central flat area 140. This provides a space between the base of the tube and the central flat area to permit the tube leads to bend and enter'the various apertures in the disk. Since the portion of the disk 10 which contains the apertures is not as deep as in disk 10, all of the apertures in disk have large entrances and have tilted axes. The tube mounting member of the invention has the advantages that it straightens tube leads and spaces and insulates the leads from each other.

I claim: 1. A mounting member for aligning, straightening, and insulating from each other, closely spaced, flexible leads of an electron tube or the like having a base from which emanate a multiplicity of at least ten closely spaced, flexible leads, and for facilitating the mounting of said tube or the like into an electrical connector or printed circuit board, said member comprising:

a disk of insulating material, the top and bottom surfaces of which being substantially planar and parallel;

two rows of lead-receiving apertures in said disk parallel and closely spaced to a diameter thereof, each of said apertures having a relatively large orifice in said top surface, and a relatively small throat ending in said bottom surface, said orifices and throats being respectively substantially equally spaced across each of said rows, each of said throats having parallel axes substantially perpendicular to said bottom surface, and each of said apertures having at least one surface tapering outwardly with respect to the center of said disk, said tapered surfaces being of decreasing steepness from aperture to aperture outwardly from the center of said disk to the periphery thereof, whereby said multiplicity of flexible leads are individually separated, straightened and positioned one from the other upon being drawn through said apertures.

2. The mounting member of claim 1 including additional apertures positioned beside said rows of apertures, each of said additional apertures having a relatively large orifice in said top surface, a relatively small throat ending in said bottom surface and at least one tapered surface therebetween.

3. The mounting member of claim 1 additionally in cluding positioning means for spacing the top surface of said disk away from the base of said tube for permitting said closely spaced, flexible leads to be spaced apart without undue bending between said base and said apertures and wherein the throats of the apertures in one row are offset from the throats of the apertures in the other row.

References Cited UNITED STATES PATENTS 2,483,351 9/ 1949 Richardson. 3,184,536 5/1965 Vincent. 3,225,262 12/1965 Myers. D. 200,157 1/1965 Vincent. 3,107,963 10/1963 Hansen. 3,388,210 6/1968 Babb.

FOREIGN PATENTS 539,152 4/1957 Canada. 405,447 7/ 1966 Switzerland.

LARAMIE E. ASKIN, Primary Examiner U.S. Cl. X.R. 317--101 

